British Airways has service to the Seychelles via Nairobi. You used to be able to go to Mauritius via Nairobi, but it is now a non-stop from London. You can get to Tahiti via Santiago with LanChile, but it's a dead end if you're on the Explorer. For the Maldives, you could fly to Bombay or Colombo then buy a R/T ticket to Male.